Generally, backpacks used for climbing or traveling each typically include a backpack body which stores objects and shoulder straps which are attached to the backpack body and go over user's shoulders.
Recently, a technology of preventing a heavy load from being applied to the back even when a lot of objects are stored in a backpack body by mounting shoulder straps on a firm back plate has been developed.
However, when a user has a backpack in which heavy objects are stored on his or her back with straps, the heavy load is concentrated on the straps. Accordingly, rucksack palsy may occur. Also, when the user has moved for a long time with an incorrect posture caused by the heavy weight, the user's body has many occurring problems.